Patents Represented by Attorney Stephen M. Roylance
  • Patent number: 4751162
    Abstract: A photoengraving article is provided formed of an essentially zinc-free magnesium-based alloy which also contains an amount of calcium effective to control lateral etching and improvement the sharpness of the resultant etched pattern. A method of forming a photoengraved article is also provided. The method comprises the steps of forming a photoengraving article from a photoengraving alloy and etching a pattern on the article in an etching bath. The improvement that comprises forming the photoengraving article from essentially zinc-free magnesium-based alloys containing an amount of calcium effective to control the lateral etching and improve the clarity of the resultant pattern. The article and method do not release zinc into the etching bath. Ultimate release of zinc into the environment is also reduced.
    Type: Grant
    Filed: August 21, 1986
    Date of Patent: June 14, 1988
    Assignee: The Dow Chemical Company
    Inventor: Geoffrey S. Newhouse